// File: contracts/AztecFeeDistributor.sol



// SPDX-License-Identifier: GPL-2.0-only
// Copyright 2020 Spilsbury Holdings Ltd
pragma solidity >=0.6.10 <0.8.0;

import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import {Ownable} from '@openzeppelin/contracts/access/Ownable.sol';
import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';

import {IFeeDistributor} from './interfaces/IFeeDistributor.sol';
import {IRollupProcessor} from './interfaces/IRollupProcessor.sol';

contract AztecFeeDistributor is IFeeDistributor, Ownable {
    using SafeMath for uint256;

    event FeeReceived(address sender, uint256 amount, uint256 assetId);

    uint256 public constant ethAssetId = 0;

    address public rollupProcessor;
    uint256 constant reimburseConstant = 16 * 51781;

    constructor(address _rollupProcessor) public {
        rollupProcessor = _rollupProcessor;
    }

    receive() external payable {
        emit FeeReceived(msg.sender, msg.value, ethAssetId);
    }

    function txFeeBalance(uint256 assetId) public view override returns (uint256) {
        if (assetId == ethAssetId) {
            return address(this).balance;
        } else {
            address assetAddress = IRollupProcessor(rollupProcessor).getSupportedAsset(assetId);
            return IERC20(assetAddress).balanceOf(address(this));
        }
    }

    function deposit(uint256 assetId, uint256 amount) external payable override returns (uint256 depositedAmount) {
        // callable by anyone, adds eth to the contract
        if (assetId == ethAssetId) {
            require(amount == msg.value, 'Fee Distributor: WRONG_AMOUNT');

            depositedAmount = amount;
        } else {
            require(msg.value == 0, 'Fee Distributor: WRONG_PAYMENT_TYPE');

            address assetAddress = IRollupProcessor(rollupProcessor).getSupportedAsset(assetId);
            IERC20(assetAddress).transferFrom(msg.sender, address(this), amount);

            // TODO
            // checks to see if any ERC20 balances can be converted to ETH on Uniswap
            // convertERC20s()
            depositedAmount = amount;
        }

        emit FeeReceived(msg.sender, amount, assetId);
    }

    function reimburseGas(
        uint256 gasUsed,
        uint256 feeLimit,
        address payable feeReceiver
    ) external override returns (uint256 reimbursement) {
        require(msg.sender == rollupProcessor, 'Fee Distributor: INVALID_CALLER');

        reimbursement = gasUsed.add(reimburseConstant).mul(tx.gasprice);
        require(reimbursement <= feeLimit, 'Fee Distributor: FEE_LIMIT_EXCEEDED');

        (bool success, ) = feeReceiver.call{value: reimbursement}('');
        require(success, 'Fee Distributor: REIMBURSE_GAS_FAILED');

        emit FeeReimbursed(feeReceiver, reimbursement);
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "../utils/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

// File: @openzeppelin/contracts/math/SafeMath.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

// File: contracts/interfaces/IFeeDistributor.sol



// SPDX-License-Identifier: GPL-2.0-only
// Copyright 2020 Spilsbury Holdings Ltd
pragma solidity >=0.6.10 <0.8.0;

interface IFeeDistributor {
    event FeeReimbursed(address receiver, uint256 amount);

    function txFeeBalance(uint256 assetId) external view returns (uint256);

    function deposit(uint256 assetId, uint256 amount) external payable returns (uint256 depositedAmount);

    function reimburseGas(
        uint256 gasUsed,
        uint256 feeLimit,
        address payable feeReceiver
    ) external returns (uint256 reimbursement);
}

// File: contracts/interfaces/IRollupProcessor.sol



// SPDX-License-Identifier: GPL-2.0-only
// Copyright 2020 Spilsbury Holdings Ltd
pragma solidity >=0.6.10 <0.8.0;

interface IRollupProcessor {
    function feeDistributor() external view returns (address);

    function escapeHatch(
        bytes calldata proofData,
        bytes calldata signatures,
        bytes calldata viewingKeys
    ) external;

    function processRollup(
        bytes calldata proofData,
        bytes calldata signatures,
        bytes calldata viewingKeys,
        bytes calldata providerSignature,
        address provider,
        address payable feeReceiver,
        uint256 feeLimit
    ) external;

    function depositPendingFunds(
        uint256 assetId,
        uint256 amount,
        address owner
    ) external payable;

    function depositPendingFundsPermit(
        uint256 assetId,
        uint256 amount,
        address owner,
        address spender,
        uint256 permitApprovalAmount,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    function setRollupProvider(address provderAddress, bool valid) external;

    function approveProof(bytes32 _proofHash) external;

    function setFeeDistributor(address feeDistributorAddress) external;

    function setVerifier(address verifierAddress) external;

    function setSupportedAsset(address linkedToken, bool supportsPermit) external;

    function setAssetPermitSupport(uint256 assetId, bool supportsPermit) external;

    function getSupportedAsset(uint256 assetId) external view returns (address);

    function getSupportedAssets() external view returns (address[] memory);

    function getTotalDeposited() external view returns (uint256[] memory);

    function getTotalWithdrawn() external view returns (uint256[] memory);

    function getTotalPendingDeposit() external view returns (uint256[] memory);

    function getTotalFees() external view returns (uint256[] memory);

    function getAssetPermitSupport(uint256 assetId) external view returns (bool);

    function getEscapeHatchStatus() external view returns (bool, uint256);

    function getUserPendingDeposit(uint256 assetId, address userAddress) external view returns (uint256);
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}